Drill stem



a June 24, 1930. BQZEMAN ET AL 1,766,326

DRILL STEM Filed April '7, 1928 2 Sheets-Sheet 1 June 24, 1930. J. F.BOZEMAN ET AL 1,766,326

DRILL STEM Filed April 7, 1928 2 Sheets-Sheet 2 Ma a 61m new A tatenteddune 24 i, lldfii? l JOHN F. soznraerr, or wnsr LAKE, LOUISIANA, ANDJ'AUDON D. COLE, or HEBRON- VILLE, 'rn

DRILL STEM Application filed April '2, 1928. Serial No. 268,192.

This invention relates to new and useful designate similar parts in eachof the Figimprovements in a drill stem. ures, the numerals 1 and 2designate the re- One object of the invention is to provide an spectiveupper and lower sections, as a whole, improved type of drill sternthrough which of the drill stem. These sections have a lim- 5 the drillbit may be rotated, with only a porited lengthwise movement relative toeach tion of the weight of the entire stem on the other, for a purposeand in a manner to be bit, at the bottom of the bore. hereinafterstated.

Another object of the invention is to pro- The upper section of the stemembodies the vide a drill stem, formed oftwo sections, the string ofpipe, as 3, having the separable weight of the lower one of which isnormally coupling 4 connected to the lower end there- 60 carried by thebit, in drilling, said stem being of, and whose lower end is reducedand, equipped with a novel type of valve whereby threaded into the upperend of the tubular the flow of fluid downwardly through the joint'5. Thelower end of this joint has a stem, from the pump, is stopped when thetubular gland 6, threaded therein whose upupper section of the stem islowered, and beper end supports the packing 7, and said 5 fore itsweight is imposed on the section bepacking is held in place by the ringnut 8 heath. vwhich abuts the upper end thereof, thereby Thisretardingof the flow of fluid will reforming a stuffing box through which theupact on the pump and thereby the operator per end of the lower section2, of the stem telewill be notified of the relative positions of scopes.This section 2 comprises a string of the two sections, before the uppersection is pipe to the lower end of which the drill bit loweredsuiiicient-ly to impose its weight on 18 is attached. the sectionbeneath, and/ the bit. The bit will The upper, or telescopingend of thelower thus never be subjected to the entire weight section 2 has anenlarged head which is 25 of the stem, and liability of crushing the bitclutched for rotation with the upper section or twisting off the stemthus is avoided. 1 by means of the vertical ribs 10, of the head Afurther feature of the invention is to 9, which fit into correspondinggrooves 11, provide a sectional drill stem so constructed in the joint 5and the re1ative movement of that the upper section may be used as a jaror the sections is limited by the ring nut 8 and 30 hammer against thelower section to dislodge the coupling 12 of the lower section 2. The

said lower section in case it becomes stuck in stem is of tubularconstruction throughout the bore. to permit the flow of flushing fluiddown- With the above and other objects in view wardly through it to thedrill bit. This this invention has particular relation to cerfluid isforced down through the stem by I 5 tain novel features of construction,opermeans of a pump 20 at the ground surface. ation, and arrangement ofparts, an example The upper end of the head 9 has an upwardly of whichis given in this specification and ilflared valve seat 13 screwedtherein, for a lustrated in the accompanying drawings, purpose to behereinafter explained. wherein The coupling 4 has an internal annular 40Figures 1 and 2 show vertical sectional shoulder 14, on which is seateda coil spring views of the upper and lower parts, or sec- 15. There is avalve stem 16, whose upper tions, respectively, of the drill stem. endcarries a spider 16 which rests on said Figure 3 shows' a crosssectional view taken spring and said stem depends through said on theline 3-3 of Figure 1. spring and its lower end carries a downward- 45Figure 4 shows a cross sectional view, takly tapering valve 17 normallyspaced above on on the line 4-4 of Figure 2, and, and adapted to seatwithin and close said seat. Figure 5 shows a side elevation of a com- Indrilling it is usually not advisable to plete stem, as in operation in awell bore. permit the entire weight of the stem to rest on Referring nowmore particularly to the the bit, atthe bottom of the bore, as in such50 drawings, wherein like numerals of reference case the bit may becrushed, or may require CII too severe torsion on the stem, to drive it,cousin "he stem to twist off.

The stem is consequently usually suspended from the rotary 19, with onlythe weight of the lower section 2 on the bit.

in drilling, the stem is gradually let down as the work progresses butit is not desirable, in lowering the stem, to permit the upper sectionof the stem to be lowered far enough to rest its weight on the lowersection. As the upper section 1 moves downwardly relative to the lowersection the valve 17 will approach the seat 13, and when the said seatis partially restricted, by said valve, the pressure above the valvewill build up thus causing the valve to overcome the resistance of thespring 15 and suddenly seat and close the passageway through the seat13, before the weight of the upper section of the stem has been assumedby the lower section. This will block the flow of the lhiid down throughthe stem and stall the pump and thus indicate, to the driller that theupper section should not be lowered further. The upper section thenshould be slightly elevated to lift the valve clear of said seat so asto again permit circulation and drilling ma Y then proceed.

In case the lower section of the stem becomes stuck in the bore, theupper section may then be dropped, successively, against the coupling 12until the stuck stem is jarred loose.

Whatwe claim is 1. A drill stem comprising two sections connected by aslip joint and having a fluid course therethrough, a seat in onesection, a yieldably mounted means carried by the other section adaptedto be actuated by fluid pressure to close said seat and block said fluidcourse when said sect-ions are relatively moved in one direction and tounblock the same when relatively moved in the other direction.

2. i drill stern including two telescoping sections having a limitedlengthwise movement relative to each other, means for interlocking saidsections against relative rotation, a projection carried by one sectionand disposed to form an abutment for the other sectiom said stern havinga fluid course therethrough, and a vieldably mounted valve attached toone section and arranged to he actuated by the tiuid flowing throughsaid course and dapted to block said fluid course when said sections arerelatively moved, in one direction, and operable by said section towhich said valve is attached to unblock the same when said sections arerelatively moved in the other direction.

In combination: a string of rotary drill pipe comprising: an upper and alower section; means for supporting said upper section; a device securedat the lower end of said lower section. said device supporting theweight of said lower section; means for atcaching said upper and lowersections together, said means being so arranged that said upper andlower sections will rotate together and may have relative axialmovement; valve means suspended from the upper section and operable byfluid pressure for obstruclin g a flow of fluid through said string ofdrill pipe when said upper section is lowered and a yieldable support,sustaining said valve means.

i. In combination: a string of rotary drill pipe comprising an upper anda lower section; means adapted to support said upper section; a cuttingtool secured to the lower end of said lower section and adapted tosupport said lower section; means for slidably connecting said upper andlower sections toether; means for creating a flow of fluid through saiddrill pipe; an inside shoulder in the upper section, valve means forobstructing said flow when said upper section is supported by saidcutting tool and a coil spring supported on said shoulder and supporting said valve means.

In testimony whereof we have signed our names to this specification.

JOHN F. BOZEMAN. JAUDON D. COLE.

